Several major approaches have been used so far for single-cell antigen cytometry. Among the most popular are single cell PCR, fluorescence activated flow cytometry, mass cytometry and single cell sequencing. These (fluorescence and mass-based cytometry) approaches are limited from either inability to breach the multiplexing levels of more than 100 parameters per analyte (cell in this case) or from inability to achieve high throughput (single cell sequencing). Also these methods are not appropriate or readily modified to enable cell multiplexed analysis of archived tissues and slide based samples.
Disclosed herein are several related methods for capture agent detection that are based on labeling the capture agent with DNA and subsequent detection of this DNA by primer extension.